Endless towing conveyor

ABSTRACT

Endless towing conveyor having a suspension track disposed below the towing chain for running carts rolling thereon, where the movable part of a coupling device is disposed between a towing chain and running carts exclusively on the drivers or dogs of the towing chain and cooperate with a curved member on the running carts which is rounded forwardly in the direction of advancement and equipped with a vertical abutment surface in the back.

United States Patent Kuwertz 1 1 Jan. 23, 1973 ENDLESS TOWING CONVEYOR[56] References Cited [75} Inventor: Erich Kuwertz, 6751 Trippstadt,UNITED STATES PATENTS Germany 3,091,191 5 1963 Fur ..104/172 5 3,024,7403/1962 Peras ..104/172 c [73] Assgnee' Pfalzsmmba GmbH Prmasem/P'3,039,403 6/1962 McDonough ..104 172 5 fall, Germany 3,541,967 11/1970Birkhead ..104/172 3 [22] Filed: Jan. 4,1971

App]. No.: 103,431

Primary Examiner-Drayton E. Hoffman Assistant ExaminerRobert SaiferAtt0rneyRobert H. Jacob [57] ABSTRACT Endless towing conveyor having asuspension track disposed below the towing chain for running cartsrolling thereon, where the movable part of a coupling device is disposedbetween a towing chain and running carts exclusively on the drivers ordogs of the towing chain and cooperate with a curved member on therunning carts which is rounded forwardly in the direction of advancementand equipped with a vertical abutment surface in the back.

11 Claims, 11 Drawing Figures PM-ENT Eflm 2 3 ms SHEET 1 BF 7' MAL/PATENTEUJAH 23 I975 SHEET 2 [IF 7 INVENTOR.

Erich KUWERTZ BY W PATENTEUJANZB I975 3.712.241

SHEET 3 OF 7 IN V EN TOR. Erich V U WE R TZ PATENTEDJAH 2 3 I975 SHEET U0F 7 PATENTEDJAHZB ma SHEET S [If 7 PATENT Emma I975 SHEET 6 [IF 7 FIG.9

INVENTOR. Erich KUWERTZ WWW PATENTEUJAH 23 I973 SHEET 7 OF 7 FIG. 11

INVENTOR. Erich KUWER TZ BACKGROUND OF THE INVENTION The inventionrelates to an endless conveyor system of the towing type. Moreparticularly the invention is concerned with an endless towing conveyorhaving a suspension track disposed below the towing chain for runningcarts rolling thereon. These endless towing conveyors constitute acombination of known endless conveyors with a towing chain guided in asuitable guide section and hand suspension tracks, also known per se,where the possibilities of coupling and uncoupling an operativeconnection between the towing chain and the individual running cartsmoving on the suspension track rails of the hand suspension tracks areof decisive significance.

In known conveyor installations the running carts are always moved alongby drivers or dogs which are secured to the towing chain with spacetherebetween. This towing chain runs continuously. The running cartsmoved by the drivers must, however, stand still at stopping stations tobe installed at any desired location, and it must be possible for themto be stacked there one behind the other. The stopping stations as arule have an entering and a release cam or curve for the coupling deviceand can be moved, for example, by means of an electromagnet into and outof the traveling track for the running carts.

Essentially the problem in accordance with the invention is based onthefact that the coupling device between the towing chain and therunning carts is so constructed that first, no movable parts arerequired on the running cart. The running carts are to be deployable innumerous ways, and their construction must not be too expensive. Forexample, if they are deployed upon manual suspension rails without anendless conveyor, coupling devices or parts thereof are not necessary onthe running carts. There is also little fundamental requirement toprovide the possibility of stacking the running carts behind oneanother. Finally, such installations as a rule have more running cartsin operation than the towing chain has drivers.

SUMMARY OF THE INVENTION The problem in accordance with the invention issolved by means of an endless towing conveyor having a coupling devicethat is constructed in such a manner that its movable parts areexclusively disposed at the drivers of the towing chain, which cooperatewith a curved member on the running carts, which is rounded at theforward end in the direction of travel and has a vertical abutmentsurface in the back.

Advantageously the caps covering the running rollers of the runningcarts serve the purpose of such curved members.

Preferably the coupling device secured to the drivers of the towingchain is defined by a housing in which a latching lever and a claw arepivotally supported for movement about coordinated horizontal axes in amanner that a lug on the latching lever in its lowered position stopsthe claw in its vertical position, and in its raised position forpivoting upwardly releases it in the direction opposite the direction oftravel, while furthermore the forward roller cap of the running carts isrounded or curved in the direction of advancement and is provided in theback with a vertical abutment surface while in the rearward roller capthe front curving is omitted.

It has furthermore been found that the possibilities of deployment ofsuch an endless towing conveyor can be essentially extended if besides aclosed conveyor circuit side branches and connecting branches orchannels are provided, which may generally be referred to as transferconveyors.

For building such an installation it is necessary, however, forchanneling the running carts rolling upon the suspension track in andout of the main circuit to provide switches between this circuit and thetransfer conveyors, furthermore means for controlling these switches,and to make provisions that the running carts rolling on the suspensiontracks of the main circuit can travel also on the transfer conveyors atas little technical expenditure as possible.

For this purpose the invention provides that in the main circuit and inthe transfer circuit there are basically equal elements such as equaltowing chains, equal drivers and equal chain guiding rails as well assuspension tracks for the running carts. This constitutes an essentialsimplification of the art because the different means mentioned are thesame in all areas of the entire installation.

Furthermore also the switch must, of course, be as simple and asreliable to operate as possible, while it requires at least oneadaptation of the running rollers of the running carts so that they cantravel on the suspension tracks as well as also along curved areas orsections.

The switch comprises essentially a switch tongue which is pivotallymovable by means of a lever which is journalled at a pivot point alongthe switch tongue and is at one end under the control of a setting ordisplacing force, and at the other end of which a pin is provided whichslides in a groove of the switch tongue, while furthermore the switchtongue is of rectangular design and provided with a flat nose at itsfree end which swings into corresponding slots of the suspension trackscoordinated with the switch.

For the power effect upon the lever that rocks the switch tongue anelectromagnet may preferably be provided, while between the magnetplunger and the lever end a spring is provided as an elastic element. Atthis end of the lever that is associated with this spring a furtherspring is provided as return pull spring.

Preferably the lever that actuates the tongue of the switch is disposedat an angle of relative to the tongue when it is turned out, so that itis stopped in the turned out position. Any lateral forces applied by therunning carts against the turned out switch tongue are thus interceptedat the pivot point and are not transferred onto the magnet.

The running rollers of the running carts have a cross section that hasan axis parallel running roller area for rolling upon the switch tonguethat has the rectangular shape and continuing inwardly a skewed oroblique area rolling upon the tubes of the suspension tracks that havecircular cross section.

Advantageously a recoil latch is provided in the tongue of the switchthat prevents the back rolling of the running carts, which could bepossible when the suspension track is not satisfactorily aligned or thematerial being carried that is suspended on the running carts pendulatesin a manner that an impulse is imparted to the running cart to runbackward.

The recoil latch is formed in a simple manner as a latch that ispivotally movable about a horizontal axis acting automatically due tothe counter weight of its lower region.

At the drivers of the conveyor chain an elastic intermediate region maybe provided which is defined by a rubber element. By means of this it ispossible if unfavorable moments should develop that the catcher or drivecan escape laterally. These rubber elements furthermore serve as asafeguard against shearing.

Finally, it must be considered that in endless towing conveyors of thistype having a suspension track disposed below the towing chain therealways exists the danger that persons and objects move into the path oftravel of the running carts, and thus these persons or objects or thematerial conveyed by the running carts can be hurt or damaged. At leastthe orderly course of the conveyor which usually is automatically guidedcan be disturbed.

Thus the problem must be solved, to provide an arrangement that effectsthe uncoupling between the driver on the towing chain and the curvedmember on the running cart when the latter or the material carriedthereby encounters an obstacle.

In accordance with the invention an uncoupling device is provided forthis purpose, which essentially comprises a downwardly extending hoop orthe like that is pivotally movable about a horizontal axis on therunning cart and has at its upper end an actuating surface thatcooperates with a roller that is mounted at the end associated with theactuating surface of an angular lever that is likewise pivotable about ahorizontal axis, and which has in the area of its other end that extendsessentially upwardly at the level between the latching lever of thedriver of the towing chain and the forward rounded portion of the curvedelement on the running cart a pin that is rockable between the latchinglever and the curved member, while a recoil spring for supporting theuncoupling device is arranged in any desired location of itsnon-operative position.

If the switching hoop encounters an obstacle, it is moved against theforce of the recoil spring. The actuating surface that is in contactwith the hoop is raised as well as the lower arm of the angular lever.The arm of the angular lever that extends substantially vertically rocksinto an oblique position. The actuating bolt at its free end raises thelatching lever of the coupling device so that the driving finger isfreed. The driving finger thus slides over the curved member on therunning cart. The effective connection between the latter and the towingchain is released. The cart stands still.

Further features of the invention will become apparent from thefollowing description with reference to the embodiment schematicallyillustrated in the drawings, in which:

FIG. 1 illustrates in a side view a coupling device with differentpositions of a running cart;

FIG. 2 is a cross section taken along line lI-II in FIG. 1;

FIG. 3 is a further side view ofa stopped running cart with a furthercart run against it;

FIG. 4 is a schematic illustration of a possible construction of anendless towing conveyor arrangement having a branch track and twoconnecting tracks;

FIG. 5 is a perspective illustration of an area of the endless towingconveyor with a switch;

FIG. 6 is a horizontal section through the switch area;

FIG. 7 is a section along the lines IVIV of FIG. 5;

FIG. 8 is a section taken in the direction of the arrows V-V in FIG. 5;

FIG. 9 is a schematic perspective illustration of the uncoupling devicein accordance with the invention;

FIG. 10 is a schematic side view of the device in inoperative position,and

FIG. 11 is the same side view with the device in operative position.

DESCRIPTION OF THE INVENTION Upon the suspension track rails 1, drivers2 on the towing chain 3 move the running carts 4 in the direction of thearrow 5. The chain runs continuously in a guiding section or profile 6,where it is guided by means of rollers 7. The carts 4, however, are tobe stopped by stopping devices 8 disposed at any desired location in theinstallation whereby also stowing of several carts, one behind theother, is to be made possible.

The suspension track rails may be secured, for example, by means ofconnecting bridges 9 on the guide section 6 of the endless conveyor;

The drivers 2 of the towing chain 3 are provided with a housing 10between the lateral side walls of which a latching lever 11 and adriving finger 12 are mounted for pivotal movement about horizontalaxes. The latching lever 11 is provided with a nose 13 which in lowerposition of latching lever 11 stops the driving finger 12 in adownwardly directed position and frees the driving finger 12 as thelatching lever 11 rocks upwardly so that it can swing upwardly inopposite direction of the advancing movement.

T he stopping device 8 comprises essentially an electromagnet 14 oranother suitable control means which can move a curved stopping member18 into the advancing track of the running carts 4 and out of the sameagainst the resetting force of a spring 16 by way of a connecting member17 disposed upon a rod 15.

If the curved member 18 is in operative position, then it raises thelatching lever 11 of the driver 2, whose nose l3 frees the driver 12,which up to then was stopped in its vertically downwardly extendingposition and thus engaged a rearward vertical abutment surface 19 of acap 20 of the front running roller 21 of the running cart 4. Thus therunning cart 4 remains standing held by the curved member 18. The driver2 may slide over the cap 20 and the curved member 18.

The cap 20 of the forward running roller 21 of the running cart 4 isrounded in front at top 22 in the direction of travel, so that thelatching lever 11 upon sliding over the cap can swing downwardly andthus stop the catching finger 12 in its vertical position.

The cap 23 of the rearward wheel 24 of the running carts 4, however, isnot rounded in front so that the latching lever 11 of the driver 2 canslide over it in the same manner as it slides over the curved member 18of the stopping device 8 and thus does not stop the top catching finger12 which in its turn slides over this cap.

If a running cart 4 is held by the curved member 18 of the stoppingdevice 8, the release mechanism of the driver 2 that brings along thenext running cart 4 acts in the same manner with the forward cap of thisrunning cart and the rearward cap of the preceding running cart as withthe forward cap thereof and the curved member 18, i.e., the latch lever11 is swung upwardly and remains upward so long, that it cannot stop thedriving finger 12. The second running cart is likewise released by thecatcher 2 of the towing chain 3 as the first running cart at thestopping device 8. This applies to all subsequently arriving runningcarts so that they can be stowed behind one another in any desirednumber.

An endless towing conveyor installation is schematically illustrated inFIG. 4 where the main stretch is indicated by dot and dash lines 31. Byway of example, a side track 32 and two connecting tracks 33 areindicated, which may be identified quite generally as transferconveyors. The endless conveyor installation is equipped with targetand/or program controls and thus makes possible completely automaticperformance. The connection between the main track and the side tracksor connecting tracks is completed by means of switches 34. In order tohave the entire installation as simple as possible, especially the sideand connecting tracks and the associated switches, equivalent elements,i.e., equivalent conveyor chains, drivers, chain guiding machines,running tracks for the main track and for the transfer conveyors areprovided.

Furthermore, in order to permit the equipment of all parts of theinstallation with equal elements, the switches between the main trackand the transfer tracks of the installation require special design. Forthis purpose it is proposed to provide in the running track 1 of thesuspension rails of the main conveyor a switch tongue 35 which ispivotable about a vertical stud 36 in the direction of a running track37 of a connecting rail or a transfer conveyor. To actuate the switchtongue 35 a lever 38 is provided, which is pivotable about vertical stud38' radially of the switch tongue 35 and which engages with its endcoordinated to the switch tongue 35 by means of pin 39 a groove 40 thatextends along the switch tongue. The other end of the lever 38 isconnected with a plunger 42' of an electromagnet 42 by way of an elasticelement in the form of a helical tension spring 41. Besides that areturn or pullback spring 43 is provided at the said end of the lever 38which at its other end is secured at any desired location of thestructure.

By means of lever 38 the switch tongue 35 can be actuated with littleexpenditure of energy, which makes possible the use of actuatingelements, for example alternating current thrust magnets, at reasonablecost.

Furthermore, the arrangement of lever 38 and switch tongue 35 is suchthat with the switch tongue 35 displaced, i.e., in the direction of therunning rail 37, the lever 38 and the switch tongue 35 include an angleof 90. Thus, the switch tongue 35 is arrested in its displaced position.If lateral forces arise as the switch tongue is travelled on by a cart4, then they are intercepted at the pivot point 38' of the lever 38 andare not transferred to the magnet 42. In order to set back the switchtongue 35, the small force of the return spring 43 will be sufficientdue to the disposition oflever 38.

If a cart 4 is switched off by way of the switch tongue 35, then itleaves the effective range of the driver 2 of the main conveyor chain 3and arrives in the effective range of an entirely equally constructeddriver 2' of a towing conveyor chain 45 of the transfer conveyor whichis merely indicated by dots and dashes in FIG. 5.

The design of the switch tongue 35 is of rectangular cross section,primarily for manufacturing reasons. By means of a rectangular sectionthe running rollers 24 can be shifted better than with a tube ofcircular cross section. The running rail proper may be in the form of atube having circular cross section, or also of rectangular crosssection.

At the free end of the switch tongue 35 a flat nose 46 is provided whichengages in the end positions of the switch tongue corresponding slottedrecesses 47 of the running rails l or 37. Thus, the switch tongue 35engages or rests at both ends and can absorb correspondingly greatforces in vertical direction, i.e., it can be of lighter construction,for example of plastic. Due to the light construction of the switchtongue the operating forces can in turn be reduced.

The running rollers 21, 24 of the running carts 4 can be adapted in asimple manner to the changing sections or profiles. This is effected inthat the double running rollers are equipped at their inner sides withrunning surfaces 57 for travelling on rectangular sections and withrunning surfaces 58 which merge with these running surfaces fortravelling on sections having circular cross section. Besides, they areprovided with flanges 59 for lateral guidance.

In order to avoid that the carts 4 roll back in the area of the switchesa recoil latch in the form of a catch 60 is provided in the switchtongue 35. Running back in this manner could occur when the runningrails of the suspension track are not properly horizontal or if thematerial that is moved is suspended on the cart 4. The cart has impartedto it a return impulse caused by pendulating. Furthermore, the cart 4must wait after release out of the effective range of the driver 2 untilit is taken over by the driver 2 of the transfer conveyor 32 or 33. Hereagain the cart could prematurely leave the effective range of the driver2 by rolling back, if the recoil latch were not provided. With automaticoperation it is necessary, however, that the cart is taken over by thenext driver of the transfer conveyor.

The catch 60 is in the form of a simple catch acting below its pivot byits own counterweight. It can, for example, be actuated by the spacingsleeve 61 on the running roller shaft 62 of the carts as illustrated inthe drawing.

Between the drivers 2 or 2' and the towing chains 3 or 45 rubberelements 65 may be provided, so that the drivers 2, 2 can evadelaterally, for example, when straightforward running carts unfavorablyencounter drivers 2'.

Otherwise, wedging of the running carts could occur. Besides, theserubber elements 65 act as a safeguard against shearing if, for example,a cart should be blocked by external conditions.

Finally, a switching hoop or shackle 74 that pivots about a horizontalaxis 73 may be provided on the cart 4 which is under the resetting forceof spring 85. At the upper end of the switch hoop 74 an obliquelyextending member presenting an actuated surface 75 is provided whichcooperates with a roller 76. This roller 76 is provided at the lowerlever arm 77 of a pivotable angular lever 78 that extends substantiallyhorizontally. The

second arm 79 of the angular lever 78 which extends substantiallyvertically upwardly carries an actuating bolt 80 or a suitably formedsheet metal part which in the position of rest engages the curvedportion 22 of the running roller cap 20.

The latch lever 11 is arched at 91 to correspond to this rounded shapeso that the bolt 80 here is located between the curved portion 22 andthis curvature 91.

In response to the smallest pressure against the switch hoop 74, themagnitude of which is determined by the form of the spring 85, theactuating surface 75 raises the roller 76 and thus the lever arm 77. Thelever arm 79 and the actuating bolt 80 are tilted forwardly. The bolt 80raises the latch lever 11 whose nose l3 frees the catch finger 12 whichslides over the cap 20. The cart stops immediately.

The angle lever 78 is pivotally secured at the roller block 82 for therunning wheel 21 associated with the cap 20. In order that this rollerblock 82 can pivot about the vertical axis 83 when travelling alongcurves, the roller 76 already mentioned is provided on the lever arm 77.As the roller block 82 is rocked, it follows a circular path on theactuating surface 75 without being raised.

Having now described the invention, the protection to be covered byLetters Patent is set forth in the appended claims.

I claim:

1. Endless towing conveyor comprising a towing chain, a suspension trackdisposed below said chain, carts having driven means movable on saidtrack, driving means comprising each as movable members a driving fingerand a latching lever on said towing chain disposed between said towingchain and one of said carts, said driven means having a curved portionat the forward end in the direction of travel for cooperation with saiddriving means and having a portion presenting a vertical abutmentsurface at the rearward end, and a stopping member below said chain inthe path of movement of said driven means.

2. Endless towing conveyor in accordance with claim 1, where each saidcart has a front and a rear running roller, and a cap covering each saidroller, and said cap on said front running roller defining said curvedportion.

3. Endless towing conveyor in accordance with claim 2, where saiddriving means include a housing that is open at the bottom in which onesaid driving finger and one said latching lever are journalled forpivotal movement about horizontal axes, said latching lever having anose retaining said driving finger in lowered vertical position andfreeing said driving finger in raised position for pivotal upwardmovement in the direction opposite to the direction of travel, and saidcap on said rearward running roller being devoid of a curved member.

4. Endless towing conveyor in accordance with claim 3, comprising a mainconveyor channel and transfer conveyor branches and switches betweensaid main conveyor channel and said transfer conveyor branches saidchannel and said branches being provided with elements of equal form ofconstruction such as equal towing chains, equal coupling devices andequal suspension tracks for carts.

5. Endless towing conveyor in accordance with claim 4, where saidswitches between the main conveyor channel and transfer conveyorscomprise essentially a switch tongue and an actuating lever for movingsaid switch tongue, a vertical stud supporting said lever biased at oneend and having a pin at the other end, said switch tongue beingrectangularly shaped and having a slot receiving said pin for slidingmovement.

6. Endless towing conveyor in accordance with claim 5, comprising a flatnose at the free end of said switch tongue and slotted recesses in theends of said suspension rail, slidingly receiving said flat nose.

7. Endless towing conveyor in accordance with claim 6, including anelectromagnet having a plunger in engagement with said actuating leverfor moving said switch tongue, a biasing spring connected to one end ofsaid actuating lever and a recoil spring connected to said endassociated with said biasing spring.

8. Endless towing conveyor in accordance with claim 7, where said switchtongue and said actuating lever include an angle of between them whensaid switch tongue is inoperative.

9. Endless towing conveyor in accordance with claim 8, where said cartsare provided with rollers having a cross-section with an area parallelto the axis for rolling on the rectangular shaped switch tongue and aninwardly connecting area for rolling on rails of circular cross-section.

l0. Endless towing conveyor in accordance with claim 9, comprising acatch in said switch tongue defining a recoil latch automaticallyactuated by the counterweight in its lower area.

11. Endless towing conveyor in accordance with claim 10, comprisingelastic intermediate areas defined by rubber elements providedintermediate the towing chain and said driving means.

1. Endless towing conveyor comprising a towing chain, a suspension trackdisposed below said chain, carts having driven means movable on saidtrack, driving means comprising each as movable members a driving fingerand a latching lever on said towing chain disposed between said towingchain and one of said carts, said driven means having a curved portionat the forward end in the direction of travel for cooperation with saiddriving means and having a portion presenting a vertical abutmentsurface at the rearward end, and a stopping member below said chain inthe path of movement of said driven means.
 2. Endless towing conveyor inaccordance with claim 1, where each said cart has a front and a rearrunning roller, and a cap covering each said roller, and said cap onsaid front running roller defining said curved portion.
 3. Endlesstowing conveyor in accordance with claim 2, where said driving meansinclude a housing that is open at the bottom in which one said drivingfinger and one said latching lever are journalled for pivotal movementabout horizontal axes, said latching lever having a nose retaining saiddriving finger in lowered vertical position and freeing said drivingfinger in raised position for pivotal upward movement in the directionopposite to the direction of travel, and said cap on said rearwardrunning roller being devoid of a curved member.
 4. Endless towingconveyor in accordance with claim 3, comprising a main conveyor channeland transfer conveyor branches and switches between said main conveyorchannel and said transfer conveyor branches said channel and saidbranches being provided with eLements of equal form of construction suchas equal towing chains, equal coupling devices and equal suspensiontracks for carts.
 5. Endless towing conveyor in accordance with claim 4,where said switches between the main conveyor channel and transferconveyors comprise essentially a switch tongue and an actuating leverfor moving said switch tongue, a vertical stud supporting said leverbiased at one end and having a pin at the other end, said switch tonguebeing rectangularly shaped and having a slot receiving said pin forsliding movement.
 6. Endless towing conveyor in accordance with claim 5,comprising a flat nose at the free end of said switch tongue and slottedrecesses in the ends of said suspension rail, slidingly receiving saidflat nose.
 7. Endless towing conveyor in accordance with claim 6,including an electromagnet having a plunger in engagement with saidactuating lever for moving said switch tongue, a biasing springconnected to one end of said actuating lever and a recoil springconnected to said end associated with said biasing spring.
 8. Endlesstowing conveyor in accordance with claim 7, where said switch tongue andsaid actuating lever include an angle of 90* between them when saidswitch tongue is inoperative.
 9. Endless towing conveyor in accordancewith claim 8, where said carts are provided with rollers having across-section with an area parallel to the axis for rolling on therectangular shaped switch tongue and an inwardly connecting area forrolling on rails of circular cross-section.
 10. Endless towing conveyorin accordance with claim 9, comprising a catch in said switch tonguedefining a recoil latch automatically actuated by the counterweight inits lower area.
 11. Endless towing conveyor in accordance with claim 10,comprising elastic intermediate areas defined by rubber elementsprovided intermediate the towing chain and said driving means.